Repellants are chemical substances, natural and synthesized, having a chemical effect on insects. Their use in human and veterinary hygiene is of great practical importance, where they protect man and beast against blood sucking, biting or otherwise annoying insects. Numerous methods and apparatuses for repelling bugs away from areas occupied by humans and animals are known and marketed throughout the United States and the world.
Known apparatuses and methods employ various means to disperse insect repellant to discourage insects from occupying certain space. One such previous device uses a heat source as described in U.S. Pat. No. 5,095,647 to disperse repellent through evaporation. Another device described in U.S. Pat. No. 5,589,181 incorporates direct application of repellent on the subject desiring relief from bothersome insects. An alternative technique, as described in U.S. Pat. No. 4,823,505, involves fogging an area with repellant to evict insects from their current location.
A drawback with the previous approaches is the indiscriminate coverage area protected by evaporation and fogging. Another disadvantage is a requirement to periodically reapply repellant to provide continuous protection.